abstract
Annual MRI and mammography is recommended for
BRCA1/
2
mutation carriers to reduce breast cancer mortality. Less intensive
screening is advised ≥60 years, although effectiveness is unknown. We
identified
BRCA1/2 mutation carriers without bilateral
mastectomy before age 60 to determine for whom screening ≥60 is
relevant, in the Rotterdam Family Cancer Clinic and HEBON: a nationwide
prospective cohort study. Furthermore, we compared tumour stage at
breast cancer diagnosis between different screening strategies in
BRCA1/2
mutation carriers ≥60. Tumours >2 cm, positive lymph nodes, or
distant metastases at detection were defined as “unfavourable.”
Of 548
BRCA1/2
mutation carriers ≥60 years in 2012, 395 (72%) did not have bilateral
mastectomy before the age of 60. Of these 395, 224 (57%) had a history
of breast or other invasive carcinoma. In 136
BRCA1/2 mutation
carriers, we compared 148 breast cancers (including interval cancers)
detected ≥60, of which 84 (57%) were first breast cancers. With biennial
mammography 53% (30/57) of carcinomas were detected in unfavourable
stage, compared to 21% (12/56) with annual mammography (adjusted odds
ratio: 4·07, 95% confidence interval [1.79-9.28],
p = 0.001). With biennial screening 40% of breast cancers were
interval cancers, compared to 20% with annual screening (
p = 0.016). Results remained significant for
BRCA1 and
BRCA2 mutation carriers, and first breast cancers separately.
Over 70% of 60-year old
BRCA1/2
mutation carriers remain at risk for breast cancer, of which
half has
prior cancers. When life expectancy is good, continuation of annual
breast cancer screening of
BRCA1/2 mutation carriers ≥60 is worthwhile.